The Diabetes in Early Pregnancy Project was designed 1) to examine the relationship between maternal diabetic control during organogenesis and malformations in the offspring, and to identify, if possible, a specific teratogenic factor or factors in the diabetic metabolic state; and 2) to compare early fetal loss rates in women with diabetes and in non-diabetic control subjects. We found that diabetic women who came into care before the period of organogenesis achieved better results than those who came in later; but their results were still poorer than for non-diabetic control subjects. Differences in maternal glucose levels during organogenesis did not explain the malformations in the offspring of the women who were followed throughout pregnancy. These results suggest that women who entered late (and were not under medical supervision during organogenesis) probably had poor control. This resulted in malformations due to hyperglycemia or related factors. The results from the diabetic group entering early strongly suggest that other teratogenic mechanisms were present. Regarding early fetal losses, we found that diabetic women in good metabolic control were at no higher risk for spontaneous abortion than control women; the risk of loss increased dramatically as diabetic control worsened; and the overall risk of losing a pregnancy was lower than expected, only 16%. Since these primary analyses were completed, a number of related studies have been completed (see previous reports). There is considerable confusion regarding insulin requirements in early pregnancy. We examined insulin doses in our diabetic women beginning at week five to determine whether there is, in fact, a fall in insulin requirements during the first trimester. Overall, we found a significant drop in insulin requirements occurring in the period from seven to eleven gestational weeks. The fall was most pronounced in those starting pregnancy in sub-optimal control. We hypothesize that the physiologic decrease in insulin requirements may be accentuated in this group by initial over-treatment with insulin when physicians attempt to improve their metabolic control in early pregnancy.